JPH11133794A - Copying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten wait time from the turning on of a power source to the actuation of the copying device by making an amount of power which is supplied to a heater smaller than a specific value in the case a copy switch is turned on during warm-up. SOLUTION: During the warm-up right after the power source is turned on by a main switch 6, two heating elements 4 and 6 are turned on in order to increase fixing temperature rapidly. When the copy switch is turned on, the heating element 5 is turned off. Using usable power generated by the turning off of the heating element 5, an original document is read. During the warm-up, the maximum power that the copying device can consume is supplied to a fixing device to rapidly increase the temperature of the fixing device. However, in the case the copy switch is turned on to request copying, the power which is supplied to the fixing device decreases. In the case, wait time is not needed because the temperature of the fixing device is increased during a period of time that an original document is read after the start of a copying operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called digital copying apparatus which reads an image of a document, converts the image into an image signal, and forms an image in accordance with the image signal. The present invention relates to a copying apparatus in which the waiting time from when the temperature of a fixing unit is turned on to when the temperature of the fixing unit reaches a copyable state is reduced.

[0002]

2. Description of the Related Art In an electrophotographic copying apparatus, a toner image is heated and fixed at about 200.degree. C. However, it takes time to raise the temperature of a fixing roller as a heating member to such a high temperature. It is indispensable that a warm-up time of several minutes is indispensable in such a copying apparatus. That is, the copying apparatus is designed not to operate until the fixing roller reaches a predetermined temperature even when the copy button is pressed.

[0003]

In a digital copying apparatus, an image reading apparatus can be operated separately from an image forming apparatus, and can be operated separately from a fixing apparatus of the image forming apparatus. However, in the conventional digital copying apparatus, since the entire copying apparatus including the image reading apparatus is not operated until the warming-up of the fixing apparatus is completed, it is not directly related to the warming-up of the fixing apparatus. The image reading has to wait until the warm-up is completed, which is a waste of time.

[0004] Due to such wasted time, the waiting time from the power-on to the start of operation of the copying machine becomes unnecessarily long, so that the copying machine is not easy to use.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a copying apparatus in which the waiting time from power-on to the start of operation of the copying apparatus is reduced.

[0006]

The object of the present invention is as follows.
In a copying apparatus having an image reading apparatus for reading an image of a document and converting the image into an image signal and an image forming apparatus for forming an image in accordance with the image signal, a fixing device having a heater capable of controlling power supply and a fixing device Control means for controlling the supply power of the fixing device, and when a main switch is turned on, a predetermined value of power is supplied to the heater to warm up the fixing device. When the copy switch is turned on during the warm-up, the image is displayed. The present invention is attained by a copying apparatus in which image reading by a reading device is started, and the control unit controls the supply power to the heater to be lower than the predetermined value.

In the digital copying apparatus, the present invention is based on the fact that reading of an image and formation of an image are performed separately, and there is a time lag between the two processes. By warming up the fixing device during the time of image reading executed prior to the formation, the waiting time from power-on to the start of the copying operation can be reduced or eliminated.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A copying apparatus according to an embodiment of the present invention shown in the drawings will be described. FIG. 1 is a block diagram of a control circuit of the copying apparatus according to the embodiment, and FIG. 2 is a flowchart of a control program of a control unit in the embodiment.

As is well known, the image reading device 2 includes a CCD sensor for reading the image of the document, a lamp for illuminating the document, a drive motor for supplying the document to the reading position, and discharging the document from the reading position. The image forming apparatus 3 forms an image by an electrophotographic method.
After forming a toner image on the photoconductor by exposure and development,
The image is transferred and fixed to form an image on transfer paper. In the present embodiment, two heating elements 4 and 5 that can be individually controlled to be turned on / off are provided as heaters for heating and melting a toner image in a fixing device in an image forming apparatus to fix the toner image. These heating elements 4 and 5 are individually turned on / off by the control means 1 as described below. As the heating elements 4 and 5, halogen lamps are used.

Next, the heating elements 4 and 5 are controlled by the control means 1.
Will be described with reference to FIG.

At the time of copying, reading by the image reading device 2 is performed in advance, and an image is formed by the image forming device 3 according to an image signal from the image reading device 2. The image formation may be started after the image reading is completed, or may be started in the middle of the image reading.

During the warm-up immediately after the power is turned on (S0) by turning on the main switch 6, the two heating elements 4 and 5 are turned on in order to rapidly raise the fixing temperature (S0).
2). The power consumption of the heating element 4 is about 1000 KVA, and the power consumption of the heating element 5 is about 300 KVA.
When the copy switch is turned on (S3), the heating element 5 is turned off, and the power consumption of the fixing device is reduced to 1000 KVA (S4). The document is read using the available power generated by turning off the heating element 5 (S5).
As is well known, document reading is performed by turning on a document illumination lamp, turning on a motor of a document feeder to feed a document to a reading position, and receiving a document image by a sensor such as a CCD. When the image reading is completed, the process returns to step (S1). If the temperature of the fixing roller does not reach the predetermined temperature and needs to be warmed up, the two heating elements 4 and 5 are turned on again to start warming up.

As shown in step (S7), when the warm-up is completed, the apparatus is in a standby state (S9), and if there is image data to be formed, image formation is performed. (S8).

As described above, in this embodiment, the maximum power that can be consumed by the copying apparatus is supplied to the fixing apparatus during warm-up, and the temperature of the fixing apparatus is rapidly increased. Is turned on and a copy request is made, a part of the heater of the fixing device is turned off, and image reading is performed using the surplus power generated by this turning off. At this time, since the power supplied to the fixing device is reduced, the rate of temperature rise of the fixing device is reduced to some extent. Since the temperature of the apparatus is raised, there is no waiting time. Since the power consumption of the image reading device is about one third of that of the fixing device, the image reading and the fixing device warm-up can be performed in parallel without any trouble.

[0015]

Since the fixing device is warmed up during image reading, the waiting time from when the power of the copier is turned on until the copier becomes ready for copying is reduced or eliminated, and the usability of the copier is improved. In addition, the copying work efficiency is improved. In particular, when copying from a large number of documents immediately after the power is turned on, warm-up is completed during document reading, and there is no waiting time for warm-up, thereby greatly improving work efficiency.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control circuit of a copying apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a control program of a control unit of the copying apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control means 2 Image reading device 3 Image forming device 4, 5 Heating element (heater) 6 Main switch 7 Copy switch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masayoshi Kanno 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation

Claims (2)

[Claims] An image reading apparatus for reading an image of a document and converting the image into an image signal and a copying apparatus having an image forming apparatus for forming an image in accordance with the image signal. A control unit for controlling the power supplied to the apparatus and the heater; supplying a predetermined value of power to the heater when the main switch is turned on to warm up the fixing device; and during the warm-up, the copy switch is turned on. And a controller that starts image reading by the image reading device and controls the control unit to lower the power supplied to the heater below the predetermined value. 2. The power supply according to claim 1, wherein the heater is constituted by a plurality of heating elements, and the supplied power is controlled by individually controlling on / off of a part of the heating elements. Copying equipment.